How to register a block template part from plugins?

[daviedR]

Since WordPress 6.7, there's a new register_block_template API which can be used by plugins to register a custom block template.

But how can we add a block template part from plugins?

[talldan]

Sorry for the delay in replying. Adding a register_block_template_part function was considered, but there's some discussion about merging the concepts of template parts and patterns, so in the future, I expect this will be possible via register_block_pattern.

[daviedR]

Thanks for your reply!
Is there any ETA on when the merging will be implemented into the core release?

[talldan]

I don't have any timeline, it's also difficult to provide a stopgap measure because of the way backwards compatibility in WordPress works.

I know there are still ways to add template parts via filters, I think WooCommerce does this, so that might be something to look into.

[daviedR]

Yes, WooCommerce does it via the get_block_templates filter. It looks a bit too complex, but I will look into it again.

[mrleemon]

Hi @talldan, checking back in on this now that some time has passed. Has there been any further progress on merging template parts and patterns, or is there a new recommended way to register template parts from a plugin in the latest versions of WordPress? Thanks!

[rajpratham1]

To register a block template part from a plugin, you can use the register_block_template_part() function (WordPress 6.1+).

You can do it like this:

add_action( 'init', function() {
    register_block_template_part(
        'my-plugin/header',
        array(
            'title'       => 'Plugin Header',
            'description' => 'Header template part added by my plugin.',
            'area'        => 'header',
            'content'     => '<!-- wp:paragraph --><p>This is my custom header</p><!-- /wp:paragraph -->',
        )
    );
});

Make sure:

• It runs inside the init hook
• The slug is unique (like my-plugin/header)
• The area matches a valid theme area (header, footer, etc.)

[mrleemon]

There's no register_block_template_part() function

[rajpratham1]

You're correct — there is no register_block_template_part() function in WordPress core.

Block template parts cannot be registered via a PHP API like blocks (register_block_type()).

Instead, there are two supported approaches:

---

1️⃣ Automatically via a Block Theme

If you're using a block theme, template parts are automatically discovered when placed inside:

/your-theme/parts/*.html

Example:

/parts/header.html

No PHP registration is required.

---

2️⃣ Programmatically via the wp_template_part Post Type (From a Plugin)

If you need to add a template part from a plugin, you must create a wp_template_part post programmatically:

add_action( 'init', function() {

    if ( ! function_exists( 'wp_is_block_theme' ) || ! wp_is_block_theme() ) {
        return;
    }

    $slug = 'my-plugin-header';

    // Avoid duplicate creation
    if ( get_page_by_path( $slug, OBJECT, 'wp_template_part' ) ) {
        return;
    }

    wp_insert_post( array(
        'post_type'    => 'wp_template_part',
        'post_title'   => 'Plugin Header',
        'post_name'    => $slug,
        'post_status'  => 'publish',
        'post_content' => '<!-- wp:paragraph --><p>This is my custom header</p><!-- /wp:paragraph -->',
        'tax_input'    => array(
            'wp_template_part_area' => array( 'header' ),
        ),
    ) );

});

---

Summary

Template parts are:

• Automatically registered from /parts in block themes
• Or stored as wp_template_part posts
• Managed by the Site Editor

There is no register_block_template_part() function in WordPress core.